1. Field of the Invention
The invention defined herein relates to the conversion of a 1,1-diarylalkane to the corresponding diarylketone without appreciably converting any nuclear alkyl substituents that may be present on the aryl portion thereof. The invention also relates to the further conversion of the alkyl substituents with concentrated nitric acid and to procedures wherein substantially all of the nitric acid employed in the process is utilized.
2. Description of the Prior Art
U.S. Pat. No. 3,075,007 to McCracken et al discloses a process wherein a diarylalkane is subjected to oxidation with nitric acid to obtain a diarylketone, particularly a diarylketone polycarboxylic acid. U.S. Pat. No. 3,479,400 to Lese et al discloses a process wherein a diarylalkane is subjected to oxidation with nitric acid in a first stage to obtain oxidation products of the diarylalkane, the oxidation products so obtained are further subjected to oxidation with additional nitric acid to obtain a diarylketone carboxylic acid and using the residual nitric acid effluent for the initial oxidation. In U.S. Pat. No. 3,641,132 to Schulz et al, nitric acid is added to a diarylalkane to obtain a nitro benzophenone.